• Technical Name
  • Fabrication Technology for SiC Superjunction MOSFET
  • Operator
  • National Taiwan University
  • Booth
  • Online display only
  • Contact
  • 李坤彥
  • Email
  • kylee@ntu.edu.tw
Technical Description The multistep epitaxial growth and high energy ion implantation technologies are used to fabricate SiC Superjunction MOSFET so that the trade-off relationship between breakdown voltage and on-resistance is overcome and the on-resistance is reduced further. In addition, the SiC Superjunction MOSFET also demonstrates the properties of high breakdown voltage and low leakage current. Therefore, the developed SiC Superjunction MOSFET can increase the efficiency of the power system and reduce power loss, volume and weight of the power system.
Project “SiC CMOS Device and IC Process Technology” was exhibited in 2019 Future Tech exhibition, which was focused on the integration of three subprojects, particularly on SiC logic circuits and drive circuits. The results were only in the lab level. This year, SiC Superjunction MOSFET has been fabricated and is ready for the commercial fabrication and will be exhibited in FUTEX2020 for the first time.
Scientific Breakthrough The developed SiC Superjunction MOSFET structure overcomes the trade-off relationship between breakdown voltage and on-resistance and effectively reduces the on-resistance. In fabrication processes, the multistep epitaxial growth successfully overcomes the low diffusion coefficient property of SiC so that the P type ions can be implanted into the N type drift region, forming P-pillar (each P type regions are connected with each other). The interface between N type drift region and P-pillar is superjunction structure which enhances the high breakdown voltage and low on-resistance and low leakage current. Therefore, the SiC Superjunction MOSFET is successfully completed.
Industrial Applicability PFC with SiC diodes can reduce 40% weight and volume; SiC diodes can reduce 60% power loss in air conditioners; the full SiC transformer can reduce 36% power loss in trains; the full SiC transformer can reduce 7% power loss and 11 tons of weight in N700S bullet trains in Japan. Tesla Model 3 also uses SiC devices to increase lifetime and efficiency (driving range).
According to Yole Development, the market value of SiC semiconductor devices will be up to 2.2 billion US dollars and the Compound Annual Growth Rate (CAGR) will be 40%.
Therefore, for the high power system, like renewable energy, EV and rail system, SiC Superjunction MOSFET can stand high voltage and reduce leakage current, leading to low power dissipation and reducing global warming.